The invention relates to a head part of an annular gas turbine combustion chamber, in whose end wall burner collars, which each accommodate a burner, are arranged in an annular fashion. The burners are each radially displaceably positioned through the use of a holding part which is fastened on the end wall together with a heat shield which is inserted into the passage opening for the burner collar and covers the end wall back side 2a toward the combustion chamber. In this case, the annularly constructed holding part, at least in segments, has flanks between which the burner collar is held using lugs arranged thereon. The holding part is placed on a ring attachment of the heat shield situated on the end wall front side.
With respect to the known state of the art, reference is first made to German Patent document DE 31 13 382 C2 (having a corresponding U.S. Pat. No. 4,322,945). In the case of the annular combustion chamber known from this document, the heat shield has a so-called attachment ring of a U-shaped cross-section which is held in the passage opening for the burner collar. However, in order to be able to mount this heat shield attachment ring at all, it must be constructed in two parts and, after the mounting has taken place, the two parts are welded together from the two sides of the end wall. In this known patent document, an edged connection is suggested as an alternative. However, both process steps, that is, the welding and the edging, require relatively high expenditures.
In contrast, the arrangement of burner collars illustrated in British Patent document GB-A-2 257 502 is easier to mount, particularly while avoiding weld seams. According to that document, each burner collar is held by way of lugs arranged thereon between flanks, provided in segments, of an annularly constructed holding part. In this case, the final fastening takes place using an elastic ring to be inserted.
Under hard usage conditions, a reliable holding by way of the elastic ring cannot always be ensured.
There is therefore needed a head part of an annular combustion chamber of a gas turbine which is functionally more reliable.
The present invention meets this need by providing a burner collar which is held by way of its lugs in a bayonet-catch-type manner between the flanks of the holding part which, together with the heat shield, is screwed to the end wall. Advantageous embodiments and further developments are described herein.
The invention will be explained in detail by means of a preferred embodiment.